Direct Drive turntables

I think that the topic of record slippage is red herring. I am not aware of any evidence (listening or otherwise) that slippage is happening. However, there is plenty of listening evidence that some phenomenon is at play that fits the concept of stylus drag audibly influencing speed stability. This evidence shows up with or without clamping.

Jj2468, I'll echo what you said about measurements. It is too complex and we don't know what to measure. Both of those statements are often true, that is why you hear them repeated so often. Some things can be measured and some cannot (at least not yet). Some measurements are useful and correlate to good sound and some do not. To the point there is something going on in the world of analog that mimics (or is) stylus drag. It can be heard but nobody to date has been able to measure it, nor have I heard of a credible technique put forth to measure it.

Actually we do have some superb, highly sensitive instruments to measure with, our ears. Too bad many tend to trust them so little.

Here's an objective test that might be done.

If one were inclined and had the knowledge and time, one should be able to take a high res digital file created from various turntables as a source and then use computer algorithms to match the signal produced there to an all digital reference master of the same material to discern the differences. Then the question would become what accounts for the differences that would surely be observed.

This would be a fun project. Maybe someday after I retire and need something to keep me busy in addition to current hobbies, including just listening to and enjoying music.

Any EE students out there looking for a masters thesis perhaps?

Jfretch,

And it's not just in the piano, listening to Phil Woods right now and this trumpet has bight, power, delicacy that I just didn't have before on my SME 20/2.

Since Phil Woods plays sax, there must be something really wrong with your table. ;)
Sorry, couldn't resist.

You want to measure stylus drag ? No problem and very easy to perform at home with little more than 5 cent material and 15 minutes time.
BTW, my comment: "stylus drag - while still kind of a nebulous issue - is best addressed by securely clamping" - contains the (obvious....) technical statement that the record should be (if possible...) part of the moving system (the platter... to benefit from energy transmission and a few other aspects) and that stylus drag as such is indeed "still kind of a nebulous issue".
Which it is as it is depending on several periphery parameters.

Anyway - the test (which result will depend on a handful of individual parameters others may list according to their respective set-up...):

Do make a small mark at the outer rim of a record (mechanical scratch, cut of small color mark - whatever - but make it very tiny).
Do make a corresponding mark at the upper outer rim of your platter so that both marks do blend.
Now go and test.
Give it a full length LP side and see what is the result.
The results will differ considerably depending on weight of LP, slippage on surface of platter, dimensions of stylus, VTF, speed and 4-5 other technical aspects in the dynamic process.
Enjoy.
I performed this test 19 years ago in length and detail and decided to simply eliminate the possibility of stylus drag and lived ever happily after.

Dear friends: IMHO we can't " live " with out measures, more on this latter on.

+++++ but the only thing that really matters is how the equipment meets your individual requirements to connect with the musicians. " +++++

" individual requirements ", this subject is the one that makes the difference and the one that makes everything extremely complex an almost impossible to have " measures " that can predict why something can/could like me or not.

I can't argue why you like something that I don't but I can argue if what you like is more or less accurate or not.

The Universe and the " Mother Nature " works with accuracy in all " orders " , with out accuracy things can end on " caos " and disaster.

In audio things are not different accuracy and accuracy levels are essential: a TT must spin at 33.333rpm not at 34.06rpm, the electrical voltage in USA has to be 117v ( or whatever. ) not 220v , a RIAA eq measurement must be accurate and measure in the 20hz to 20Khz range not between 10hz and 12Khz, etc, etc.

Measure accurate measures help to the audio item designer to know and meet his design targets, he needs to measure and try to design with accuracy on: frequency response, noise level, harmonic distortion, etc, etc,
Today it is extremely rare that an inaccurate audio item can sounds great, of course that due to our each one " individual requeriments " could sounds great but this is not the overall subject.

Me like all of you likes " good sound " / " emotional sound " but I like more ( an always looking at. ) accurate " good/emotional sound ".

There are a lot of good electronics that " sounds good " but are or have serious inaccuracies: amplifiers with high output impedance ( say over 0.5 ohms. ), amplifiers with differences on its frequency response and output voltage on both channels, same with line stages, phono stages with RIAA eq deviation over 0.1db ( designers of phono stages with RIAA deviation on the 0.5db that not only does not cares about but that are proud of that spec!!!!), snesible differences between channels in frequency response and RIAA eq deviation in phono stages, etc, etc, etc. I say inaccuracies that put severe colorations to the sound we are hearing.

I'm very sensitive to inaccuracies/colorations and I'm training/trained to detect very fast and do not tolerate when I can do something about. Some of you know that this " tool " is true because I was at your places and speak on system " colorations ".

Because I like accuracy and neutrality do you think that I don't like " good/emotional sound " ?, " good/emotional sound " is my prime target along accuracy.

Many of us that have " good/emotional sound " even not know how accurate is that sound and many times we don't care about.

The MUSIC has the magic to move us even through a " walkman " in the subway but this is not the subject either.

For me it is a myth that measures has nothing to do on what we are hearing and I have to add: if you know what you have to measure.

When we were on our self Phonolinepreamp design and before ( way before ) we start to hearing it we use the more digital/computer advanced tools/models to " measure " each single stage on our design from different approaches: noise level, THD, IMD, bandwindth, frequency response, etc, etc. We made it first to have what a " perfect model " predict on performance at each single electronic stage, second for when the first unit was build we can compare real measures looking for differences against that " perfect model ", third to have standard measures if we want to build more than one unit, fourth to guess how beat those measures through design or changes on parts.
We made several scientific tests looking for differences between a signal at the input ( with out any electronic line stage process. ) against that signal at the line stage output.
With out tests, measures and the like we are in hand of " random " ( like many people " likes " to " live ". ), accuracy?: what's that?

I'm the " harder " critic of what I hear/heard in my audio system even harder that what I can be with other people systems. I hate mediocrity but I hate more when the people accept that mediocrity.

Like I say: I like " good emotional sound " but I like more accurate good emotional sound!!!!

Regards and enjoy the music,
Raul.